US2255918A

US2255918A - Well pump

Info

Publication number: US2255918A
Application number: US319341A
Authority: US
Inventors: Harold R Downs
Original assignee: Individual
Current assignee: Individual
Priority date: 1940-02-16
Filing date: 1940-02-16
Publication date: 1941-09-16
Anticipated expiration: 1958-09-16

Description

H. R.- DOWNS WELL PUMP Sept. 1 6, 1941.,l

Filed Feb. 16, 1940 3 Sheets-Sheet@ 2 @we .J

ATTORNEY y 0, y V 4.///

3 Sheets-Sheet WELL PUMP H. R. DOWNS Filed Reb. 1e, 1940 Sept. 16, 1941.

n uw n .vldmazf ATTORNEY? INVENTOR ,CW Y m Sept. 16, 1941. H. R; DOWNS 2,255,918

VWELL PUMP Filed Feb. 16, 1940 l 3 sheets-sheet 3 Bry? 1 IN1/EN TOR. 7a/oldi?. aw

ATTORNEYS.

Patented Sept. 16, 1941 UNITED STATES PATENT OFFICE WELL PUMP Harold R. Downs, Tulsa, Okla.

Application February 16, 1940, Serial No. 319,341

8 Claims.

This'invention relates to improvements in a uid operated deep well pump, and more particularly, but not by way of limitation, to means for intermittently admitting the discharge of the actuating fluid for the pump into the eduction tube of the well. This application is a continuation in part of my co-pending application Serial No. 263,022, filed March 20, 1939.

In the particular embodiment shown in my co-pending application supra, a bottom hole rotary pump is driven by a fluid actuated rotary motor to which the actuating fluid, such as gas or air, is automatically controlled by a metering or regulating device. The metering device maintains a pressure differential across the rotary motor sufficient to operate the pump lat maximum speed regardless of any variance in pump load. This is accomplished by the cooperation of the motor input and discharge fluid pres sures with a plurality of 'floating pistons regulating an input orifice. The motor discharge fluid in addition is injected into the flow line from the rotary pump to assist-,the work of the pump by gas lifting the fluid load.

In the aerating or gas lifting of oil from an oil well, normally a fluid such as gas or air is injected in a vertical column of liquid at or near the base of the liquid, and at a pressure somewhat exceeding the static pressure at the point of injection, and in suiicient volume to cause an upward movement of the fluids in the column. With the gas reaching higher levels in the column or the eduction tub'",'a gradual expansion of lthe gas takes place to create a constantly increasing ratio of gas to oil. Injected gas under normal conditions is relatively constant, and the speed of the gas and liquid in the eduction tube will increase until an area of constant pressure (such as atmosphere) is reached, or the friction of the liquid against the walls of the eduction tube will inhibit further increase in speed. Recovery of oil from Wells by aerating can be maintained pro- -vided the up-rushing and expanding gas does not entirely free itself from the liquid during its upward travel in the eduction tube. j

Gas introduced at the base of a column of liquid at a given pressure and through av definite orifice establishes a definite volume of inputgas entering the column of oil. This volume of gas at its input pressure Will raise the surface of the oil in the column, and, since the gas constantly expands upon reaching higher levels, will extend the column of oil by its original input volume times the ratio of expansion.

It has been found that bubbles of air or gas rising through a liquid are required to expend a definite amount of energy to force their way to the surface, or conversely, a liquid in a column expends an amount of energy when it freesvitself of entrapped air or gas bubbles by a process of the heavier gravity liquid displacing the lighter gas.

In pneumatically aerating a column of oil, the larger bubbles of gas rise quickly and the small bubbles more slowly so that in highly viscous liquids, such as crude oil, it has been found that bubbles of definite size may be arrested. In viewV of this, air or gas injected into an eduction tube for lifting a column of liquid will expend its compressed energy more effectively if the volume of gas enters the liquid in the greatest number of bubbles possible. In other Words, if the gas enters the liquid in such a manner as to create the greatest amount of molecular film or surface tension in the liquid with relation to its volume, the greatest amount of energy will be expended by the gas and the liquid in the process of separation. It is thus apparent that in an oil well to to be produced by gas lift a thorough breaking up of the oil mass into finely divided gas and oil particles by means of turbulence or agitation will cause an infinite number of bubbles to continuously displace the oil and move upward, thereby allowing the gas and oil mixture to be lifted in the eduction tube at a lower gas speed due to the original volume of compressed. gas injected, and also to expansion of the gas. Furthermore, the greatly increased area of the frothy gasv and oil acts as an impedance to gas flow, as compared to larger bubbles of oil (of greater weight in relation to the surface area) having less resistance to the lifting energy of the gas stream.

In a gas driven motor actuating a fluid pump of the type disclosed in my co-pending application mentioned supra, the discharge gas from the actuating motor-is'utilized to assist the pump in lifting the column load, and thus obtain the greatest lift efficiency in producing oil from a well hole. By injecting the discharge gas of the motor into the 'fluid stream in such a manner as to thoroughly agitate and provide a foamy or` frothy gas and oil mixture, the column load is substantially lightened. However, the speed at which the discharge gas from the motor is injected in to the eduction tube must be given con-l E sideration since the pump will produce a pressure head of oil at the point of injection, and' if the volume of gas and its speed of flow into the eduction tube is to be maintained, a sufficient` pressure 'differential across the gas driven motor must be maintained. As disclosed inv my co-pending application, the constant pressure differential for the motor for any` varying pump load is accomplished -by the iiuid regulator or metering device where input gas pressure is metered to the motor in relation to a discharge pressure from the motor so as to supply the necessary torque to the ro`- tary pump shaft at any load variation. The

maintaining of an unlimited higher input gas,

pressureabove the motor to meet the demands of the metering device, as to pressure differential, assists in controlling the volume and speed of the motor discharge gas entering the eduction tube regardless of the pressure head in the eduction tube.

It is therefore an important object of this invention to increase the lifting efficiency of 'a bottom hole pump by injecting the discharge iiuid from a fluid motor actuating the pump into an eduction tube in such a m'anner as to cause an infinite number of gas bubbles to continuously displace the pumped liquid slowly upward, due partly to the original volume of gas injected, and partly to the increasing volume of gas during its expansion in vertical travel upward in -the eduction tube.

A further object of this invention is to produce liquid from `deep wells wherein the weight j of the column of liquid is decreased by main-- taining pressured gas in an intermingled or occluded state' in the liquid.

And still an additional object of this invention is to produce a stream of frothy oil-and gas from an oil well by introducing the discharge an orifice which can be alternately opened and closed so that the gas will be intermittently injected into the column of liquid to eiiiciently foam or froth the liquid column and thus lighten the column load.

And still a further object of this invention is to efficiently gas-lift a column of oil by lightening the column load through an intermingling or hatching of pressured gas with the oil in such a manner that the gas discharges through a multiple apertured orifice at a speed fmany times greater than that of the oil travel,

and at a pressure slightly in excess of the oil at the point of gas discharge.

lAnd another object of this invention is to assist a' fluid operated pump in lifting a column of oil from a' well hole by directing a stream of high pressured gas actuating the pump into vthe, column so that the gas contacts Vthe oil and causes it to form a frothy mixture of gas and oil before the gas loses a considerable percentage of its density or expands to a lower pressure range.

And a further object of this invention is to produce oil from a well hole by discharging high pressure gas into intimate contact with a stream of oil being pumped in an eductionl tube to form a frothy mixture of gas and oil presenting v the greatest "wetted area of oil, which shall prevailfrom the bottom to the top of the eduction tube. -1 l And another object of this invention is to produce oil from a well hole by injecting discharge gas from a fluid motor `actuating a uid pump into the stream of oil being pumped so that a proper ratio of gas and oil can be established' to deliver the gas freed by a surface separator in a state of ultimate oil saturation.

And still another" object of vthis invention is to direct a stream of high pressured gas into a column of oil in such a manner as tol cause foaming'of the oil whereby continuous flow of gas through the frothy or emulsified oil will natural gasoline absorption of gas or the absorption of lighter hydrocarbons from the oil by the gas.

Other objects and advantages of the invention will be evident from the following detailed description readin conjunction with the accompanying drawings which illustrate one form of my invention.

In the drawings:

Fig. 1 is avvertical elevational view of the invention shown supported in the tubing of a well hole.

Fig. 2 is an enlarged fragmentary sectional elevation of the pump unit showing parts of the motor and rotary pump.

Fig. 3 is'a sectional elevational view of the unit taken at a point below the motor, and showing the valve means as taken on lines 3-3 of Fig. 4.

Fig. 4 is a View taken on lines 4--4 of Fig. 3.

Fig. 5 is a detail view showing the outlet orifices for the gas and oil taken on lines 5-5 of Fig. 3.

Fig. 6 is a sectional elevational view of a modified form of the unit-showing the uppermost portion of the pump housing to include a plurality of apertures.

Fig'. 'l is a view similarto Fig. 3 showing a modied form of construction with the valve unit omitted.

Referring to the drawings in detail and more particularly to Figs. 1, 2. and 3, the pump unit is shown disposed in a well hole provided with a casing 2 and a string of tubing 4. 'The lowermost section-of the tubing 4 is of special construction having an enlarged portion 6 formed at its lower end with an annular projection 8 for receiving an annular ring or gasket lll upon which the pump, cylinder or housing l2 is supported. The pump mechanism proper is contained within the housing I2 and comprises three units, a control regulator or metering device (not shown), the iiuid driven rotaryv motory and the pump unit proper, which are described in detail in my co-pending application mentioned supra,

The uppermost 'portion of the pump housing l2 is provided with an anchor I44 for facilitating removal of the unit from the well hole. proximity of the anchor the housing is provided with a plurality of apertures I6 through which input fluid under pressure,l such as gas or air,

. is directed through tubing 4, from a source or.

supply such as a 'compressor or. the like, at the surface of the well (not shown). 'I'he fluid is directed into an inner cylinder I8 welded at 20 to the inner periphery of the housing I2, yhence downward into a dual channel or conduit 22 communicating with an apertured block or manifold 24 having its interior forming a conduit 26. The. block 24 is threaded to a lower manifold 28 in which is disposed a spring urged ball check valve 30. A cylindrical conduit 32 extends from the manifold 28 into communication with the regulator Vor metering device of the unit (not shown) but disclosed in my co-pending applicationmentioned supra.

A rotary motor is disposed below the fluid regulator and comprises a vertically disposed rotat-b able shaft -34 journalled in suitable bearings 36 (the upper bearings are not shown, see Fig. 3) secured within the pump housing I2. The shaft 34 is provided with a plurality of radially extending motor vanes 38 adapted to be actuated by the input fluid as to be hereinafter set forth. As shown in Fig. 3, the motor shaft 34 is connected by a suitable coupling 40 with a exible pump shaft 42, which in turn drives the pump rotor 44, moving in an eccentric path with a stator 46 of the pump. The pump is described in detail in my copending application and is of a construction similar to a patent granted to Moineau, No. 1,802,217, and the novelty of this invention is not limited to 4this particular structure, it being understood that any suitable type of rotary pump for displacing fluid could be utilized in lieu of the particular structure shown..

Referring to Fig. 3, the shaft 34 is shown extending through an apertured bearing block 48 disposed in the housing I2 below the motor vanes 38. Packing 50 surrounds the shaft 34 and is held in the apertured block by a packing nut 52. Immediately below the block 48 is a valve unit 54 secured by the pin 56 to the shaft 34 so as to be rotated simultaneously with the shaft as will be hereinafter set forth. 'I'lie lower end of the motor shaft 34, the pump shaft 42, and the valve unit 54 are disposed in a cylindrical block or housing 58 threaded at 60 and 62 to sections of' the pump housing I2 so as to be arranged therein. An uppermost portion of the housing 58 is provided with an enlarged recessed portion 64 in which is disposed the valve unit 54. A portion 56 of the inner periphery of the recess 64 acts as a. valve seat for the rotary valve for a purpose as will be hereinafter set forth. v

A port or conduit 68 is provided inpthe block 48 and provides communication betweenl the discharge outlet of the motor and housing 58, so that discharge gas from ,the motor is directed through the conduit 68. intoj the housing 58 for a purpose as will be hereinafter set forth.

The manifold or housing 58 is provided with a plurality of circumferentially spaced ape'rtures 1li (Fig. 4) disposed immediately above the seat portion 6B, and in communication with the port 58. Preferably six apertures are provided, how-` will be hereinafter set forth.

' The valve 54 is provided with a recess or groove 16 adapted to intermittently communicate with a set of each of the ports and 12 to allow com munication of the discharge iiuid pressure from the motor with the port 14. The operation of the valve 54 simultaneously with the'rotation of 80 (see'Figs. l and 3) providing communication between the interior 82 of the housing 58 and a space 84 between the housing 1?; and the tubing 6.` The outlet ports 80 allow discharge of oil pumped into the chamber 82 into the space 84.

In order to assist the lifting of the oil load in the space 84, the discharge gas from the rotary motor is directed into the oil stream to pneumatically aerate the column of oil upward. In order to direct the discharge gas into the oil stream the conduit 14 is in communication with an annular channel 85 which in turn communicates with a plurality of vertically disposed ports 88 dividing the gas into smaller bubbles and directing it to the outlet ports 88 (see Figs. 3 and 5). Displaced oil discharging through an outlet port 80 is 'immediately contacted by the discharge gas from ports 88 so that the outlets 88 act as agitating or` hatching chambers wherein theoil and gas is thoroughly mixed to cause a frothy mixture in the column load. The pethe shaft 34 to intermittently place the groove 16 inalignment with a set of ports '10 and 12 allows the discharge iiuid from the motor to be periodically discharged into the port 14 for a riodical or intermittent discharge of the finely divided gas directed into the outlet ports provides a rapid percussive thrust of gas pressure at a definite speed to thoroughly agitate and froth the oil, It will be apparent that the discharge gas is maintained at a pressure slightly higher than the oil load so as to assist in the lifting of the oil, as fully disclosed in detail in my coso that the gas is thoroughly broken up into an -infinite number yof small bubbles to materially increase the lift eiiiciency by the elimination of large coalesced volumes of gas.

Operation Although it is thought that the operation will be apparent from the `above detailed description, a brief rsum of the operation is as follows: I

Input uid such as gas or air at a suicient pressure is discharged through the apertures II. ball valve 30 and into the meteringdevice (not shown) controlling the speed and volume of the actuating fluid for the motor in a definite ratio to the torque demanded f thevmotor shaft 34 by the pump load. The rotation ofthe motor blades 38 by the actuating fluid with a consequent rotation of shafts 34 and 42 causes the rotor 44 to move in an eccentric path with respect to the stator 46 of the pump. In this manner uid in the shot hole isdisplaced bythe pump into the area 82 to be discharged through the outlet ports 8E.

The discharge gas from the rotary motor in addition to assisting the control of the metering device as disclosed in my co-pendifig application mentioned supra Vis likewise directed into the Port 6B Where the simultaneous rotation of the valve 54 with shaft 34 allows a ,periodic discharge of the motor discharge gas into the ports l, 86 and 88. This periodic or intermittent discharging of gas throu'h the valve unit 54, as well as the breaking up of the gas 4streamby the ports 8B, imparts to the pumped oil high velocity concussions or Ivibratory shocks of nely divided gas which immediately agitates the oil to cause a frothy mixture of 'gas and loil. The

Bas and oil mixture dischargingfrom the outlet ports 80 into the space 04 discharges through the apertures 90 (Fig. 2) into -the space 92 between the tubing 4 and the casing 2. The aperture 90 provides for a further .breaking up of the gas and oil mixture to deliver the oil into the eduction tube `in a condition of greatest efilciency for lifting.

In the continued operation, with an 'increase in pressure head or column load, the unit automatically provides an increased motor discharge pressure so as to inject an increased proportion of high pressured discharge gas into the column. and aecting an increase in speed throughout the column vto reduce slippage or frictional resistance. Suitable packing 94 prevents discharge of the mixture into the tubing 4, while suitable packing 96 between the tubing and casing 2 blocks oi! the pumped oil from the shot hole. l

Fig.6 is a modification showing a mixing'or hatching of the discharge motor gas and oil in the uppermost part of the unit. Itwill' be understood that in this modication the valve unit of the preferred embodiment is preferably eliminated and exhaust gas inthe motor communicates directly into the uppermost portion of the unit'. The pump housing V|00 comprises two cylindrical sections |0| and |02 of diierent diameters connected by anintegral portion |04. The housing |00 is preferably disposed in spaced relation in two lowermost sections of well tubing |05 connected together by a collar |06 having a recessed portion |08. A .vertically extending cylinder ||0 issecured 'at to the collar |06 and acts as a liaiile for a purpose to be hereinafter' set forth. A cylindrical block ||2 is dis-- posed within the housing |00. A spring urged ball check valve I'I4 is disposed in a recessed portion H5 of the block ||2. *In-put iiuid for actuating the motor as shown in the preferred embodiment isdirected through the valve H4,

a conduit ||6 provided in block |I2, into the in'. terior H0 of a cylinder |20 disposed within the housing and secured in any suitable manner to the lowermost portion of the block I I2. A floating screen |22 is disposed in the u chamber |'|0 and acts to catch any debris which may be present in the in-put` iuid.A The oating arrangement of the screen is provided by a helical spring |24 and apertured washer |26 anchoring one end of the screen. It -will' be understood that the lower portion of the filter (not shown) isanchcred in a manner similar toI the upper portion such as the spring |24 and washer |26 in y order to provide the floating arrangement of The spaced relationship of the block ||2 and housing portion |02 provides a chamber |24` communicating with the discharge side of the motor (not shown) thereby providing direct passage of discharge fluid pressure from the motor through chamber |24 and outlet ports |21 arranged in the uppermost portion of block ||2. It will be apparent that the pump unit las vshown in the' preferred' embodimentldisplaces the oil through a space |20, apertures |30 provided in the cylinder |I0, hence into the chamber |02 be tween thev housing and the tubing. A floating ring |34 is disposed on the periphery of the cylindrical block ||2 above the outlet ports |21.

The ring acts as'a check' valve for 'gas discharging through ports |21.. The inclined portion |04 is provided with a plurality of` apertures |36 and dischargedgas pressure from the motor is directed through the apertures |36 causing a breaking up or dissemination of the gas into finely divided particles prior to being batched, 5. or mixed, with the oil present in thechamber |32. It will be apparent that the shouldered portion |30 of the baille agitates the oil discharging through ports |30 to assist in the forming of a frothyv mixture of gas and oil.

As illustrated in Fig. 7, the valve unit of the preferred 'embodiment is eliminated from the motor shaft 34a and. as in the preferred embodiment, discharge fluid pressure from the. rotary motor is directed through ports |50 into a space l5 |52 providedv by cylinder |54, hence through a plurality of apertures |56. The apertures |56 break up the gas into finely divided 'particles 'prior toimixing with the displacedoil in ,space |60. The frothy mixture is discharged through outlet ports |62 into the eduction tube or tub-- Fromthe foregoing it will be apparent that the invention establishes an increased efiiciency for a combination pumping and gas lifting of oil from a well hole by the thorough mixing of a continuous stream of pumped oil with high pressured gas or air whereby the oil in the eduction tube is .broken up into a minutely divided mixture of gas and oil bubbles to aifect an increase in speed of the pumped mixture in the column, which in turn decreases slippage of oil particles due to friction. Furthermore, imparting to the gas to be injected frequency interruptions inthe form of pressure percussions. in turn imparts to the pumped oil vibrations for agitating the oil and causing the forming of a frothy or emulsiiled gas and oil mixture whereupon the pumpedload is materially decreased to affect the lifting efliciency, and at the same time 40 -provide fa mixture `of.gasoil saturation so that freed gas at the top of the well is afforded the greatest oil absorption, which is advantageous in the recovery of liquifiable constituents from the .gas by cracking. Changes may be made in the combination and arrangement' of parts as heretofore set forth in. .the specication and shown in the drawings, it being understood that any modification in the precise embodiment of the invention may be Aa made within the scope of the following claims without departing from the spirit of the invenf tion. j

What I claim is: u l. In anl oil lifting apparatus comprising a gas driven motor having a shaft for driving a rotary L pump, means providing communication between the discharge side of the-motor and theoil being pumped, and means mounted on the motor shaft and cooperating with the communicating means to allow periodicthrusts of motor discharge gas into the oil vstream to cause a frothy mixture of gas and oil. 'u

2. In a pump mechanism, a pump unit driven by a fluid actuated motor, means providing communieation between the motorA and the liquid being pumped to allow motor discharge iluid to pneumatically displace the liquid, a valve actu-4 ated by the motor for causing periodic thrusts oi' motor discharge fluid into the liquid stream whereby the pumped liquid i's agitated to form f a frothy mixture of gas and oil.

3.A In a pump mechanism, a pump driven by a 'fluid actuated motor, means providing communis cation between the discharge side of the motor and the liquid being pumped. a valve interposed in the communicating means and actuated by the motor for causing a. periodic ilow of motor discharge fluid into the liquid stream, and means for breaking up the discharge pressure into finer particles andcooperating with the periodic fluid flow to cause agitation of the pumped liquid and form a frothy mixture of fluid and liquid.

4. In a liquid lifting apparatus comprising a cylinder disposed in the tubing of a well hole, a rotary pump arranged in the cylinder, la fluid driven motor disposed in the cylinder and having a'shaft for actuating the pump, a cylindrical housing disposed in the cylinder between the motor and the pump, a recessed valve mounted on the shaft and arranged in the housing, communicating means between the discharge side of the motor and the valve, communicating means between the valve and the liquid to be pumped,

Cil

a plurality of ports arranged in the housing l and cooperating with the recessed valve to allow periodic discharge of motor fluid into the liquid stream. Y r

5. In a liquid lifting apparatus comprising a cylinder disposed in the tubing of a well hole, a rotary pump arranged in the cylinder, a fluid driven motor disposedin the cylinder and having a shaft for actuating .the pump, a cylindrical housing disposed in the cylinder between the motor and the pump, a recessed valve mounted oil and gas mixture. 1

6. In a lifting apparatus-comprising a cylinder disposed in the tubing of a well hole, a rotary pump arranged in the cylinder, a fluid driven motor disposed inthe cylinder and having a shaft for actuating the pump, a cylindrical hous--` ing disposed in the cylinder between the motor and the pump, a recessed'valve mounted on the shaft and arranged in the housing, a conduit providing communication between the discharge side of the /motor and the valve, a second conduit providing communication between the valve' ,and the liquid to be pumped, aplurality of ports arranged in the housing and cooperating with the recessed valve .for periodically discharging the motor discharge" fluid into the liquid stream to cause agitation of the pumped liquid, a plurality of small ports formedy in the last'mentioned conduit to break up the periodically flowing fluid linto minutely divided particles to form a frothy mixture of gas and oil.

'7. In a well pumping apparatus comprising a cylinder disposed in well tubing arranged in spaced relation to the casing of a well hole, a

rotary pump arranged in the cylinder,'a fluid driven motor disposed in the cylinder for actuating the pump, means providing communication between the discharge side of the motor and the liquid being pumped whereby discharge fluid' pressure from the motor is utilized to pneumatically displace the pumped liquid, means for pe. riodically thrusting .the discharge fluid into the liquid stream, means for disseminating the discharge fluid into"v small bubbles prior to vinjection into the liquid stream, and means provided in the tubing 4for further diffusing theI mixture discharging into the casing. y

8. In a bottom hole rotary pump actuated by a fluid driven motor automatically receivingactuating uid at a speed and volume necessary to actuate the motor for any particular torque required by the pump, means providing communication between the 'disharge'uid outlet of the. motor and the liquid to be pumped, means interposed in the communication means `for creating a'periodic flow of the discharge fluid of the motor into the liquid stream, and means provided in the communicating means for disseminating the discharge uid into smaller bubbles' prior to injection into the liquid to be pumped, said last mentioned means cooperating with the periodic flow to cause agitation of the liquid to be pumped for forming a frothy mixture.

HAROLD R. DOWNS.